Single-File: Run from Bundle

Single-File: Run from Bundle

This change implements:

* Runtime changes necessary to load assemblies directly from the bundle:
    * Design notes about [Load from Bundle](https://github.com/dotnet/designs/blob/master/accepted/2020/single-file/design.md#peimage-loader)
    * Most of these changes are directly from https://github.com/dotnet/coreclr/pull/26504 and https://github.com/dotnet/coreclr/pull/26904

* Hostpolicy change to not add bundled assemblies to TPA list:
    * Design notes about [Dependency Resolution](https://github.com/dotnet/designs/blob/master/accepted/2020/single-file/design.md#dependency-resolution)
    * TBD (separately) items: Fix for hammer servicing #36031

Fixes #32822